Naruto: Reincarnation With All Existence System

After Ren got guided to the library he realized that it wasn't a normal library. The library had no normal books, only scrolls and nothing was saying what these scrolls were about, also the scrolls seemed to be staying on shelves that were crudely carved into the cave walls. Since nothing was saying what each scroll was about Ren decided that he would just randomly take a scroll and if that didn't work he would use All Existence to figure out what each scroll is about. Once Ren began to look at the scrolls he realized that not all of them were about sound techniques instead some scrolls were about how the demon bats fight, and some scrolls even talked about other demon clans.

After looking around for about ten minutes Ren now had five scrolls picked out that he decided to read. The first scroll was about the geography of the land of demons, but it also included where other demon clans had been spotted. Then the second scroll that Ren found was about the history of the demon clans. What was in this scroll greatly surprised Ren because it talked about how all the demon clans used to live in a place they called the underworld, but the underworld had many beings even stronger than the demon clans so they all got together and then found a way to get to this world.

Then once they were in this world they had fought each other for a long time, then during this fighting, a dark demon called Mōryō had absorbed the other dark demons. After absorbing all the other dark demons Mōryō had greatly grown in strength and then made an army of shinobi who were in a pact with him and began to try to destroy the world. Then as all the demon clans were beginning to think the world was going to end Mōryō had gotten sealed by a priestess, and since this power scared the demon clans they all went into hiding.

The third scroll was about the other demon clans. From this scroll, Ren learned that there were a total of 13 demon clans, including the dark demon clan which was now only Mōryō. The first clan it talked about was the dark demon clan and they had the power to control darkness in many different ways, they were also considered the strongest demon clan. The second clan is the spirit demon clan, the spirit demon clan was mostly unknown and all that was known about them was that they had the power to become formless and could attack past someone's physical defense, and it was considered the second strongest clan. (AN: I am about to give an info-dump about all the demon clans, so skip a few paragraphs ahead if you don't want to read about that but it will probably be important in the future)

The third strongest clan was the void demon clan, the void demon clan could manipulate space, also after all the demon clans went into hiding the void demon clan hadn't been spotted and have been thought to now be extinct. The fourth strongest clan was the demon bear clan, this clan didn't have any special abilities but their physical body was considered the strongest out of all the clans. The fifth strongest clan was the demon eagle clan, and this clan could manipulate wind and it was rumored that their eyes could see near the molecular level. The sixth strongest clan was the demon bat clan, this clan was only slightly stronger than the demon owl clan, and the clan could manipulate sound and also could get slightly stronger by drinking someone's blood.

The seventh strongest clan was the demon owl clan, and this was the same clan that Ren went to and had a rivalry with the demon bat clan, this clan could move nearly silently and could reinforce their wings. The eighth strongest clan was the demon wolf clan, and this clan had a strong physical body, slight night vision, and worked together in small groups. The ninth strongest clan was the demon gorilla clan, this clan had a strong physical body but they didn't like fighting others instead they liked staying together and were more peaceful compared to other demon clans. The tenth strongest demon clan was the demon spider clan, this clan could control and make webs that could easily trap people but their body was very weak compared to the other demon clans.

The eleventh clan was the demon crow clan, this clan didn't have any special abilities but were normally in large groups and once they spotted blood they turned berserk. The twelfth strongest clan was the demon turtle clan, this clan had a very powerful defense but they didn't have a good attacking ability. The thirteenth strongest clan was the demon panda clan, this clan was peaceful and possessed an intelligence a lot higher than other demon clans, there was also a rumor that they had a technique to tell the future. The last scroll that Ren got contained four different sound techniques, the first technique was called the sound emotion jutsu, the second technique was called the voice changing jutsu, the third technique was sound barrier jutsu, and the last technique was sound clone jutsu.

The sound emotion jutsu works by producing sounds at different pitches that can influence someone's emotions. The voice changing jutsu acted exactly as it sounded, the jutsu let someone change the sound that their voice makes, which can let them sound like others. The sound barrier jutsu had two different effects, the first effect happened from making powerful sound waves circle around Ren to block attacks, and the second effect was that whatever sound happened inside the barrier got disrupted by the powerful sound waves circling Ren, so anyone outside couldn't hear what happened inside the barrier. The sound clone jutsu was completely different compared to other clone jutsu, this jutsu would make an invisible clone made of sound, the sound clone wasn't very powerful but since it was invisible it could sneakily attack someone or work as a spy.

*Three days time-skip*

It has been three days since Ren began to learn the jutsu in the scroll. Now Ren was able to use all the jutsu and read all the other scrolls, so Ren decided that it was time to learn more jutsu. This time around Ren only got scrolls in how the demon bats used their bodies because Ren had part of their bloodline and he knew eventually he would have some traits similar to theirs. After understanding how the demon bats used their bodies, Ren decided that he would leave the demon bat lair to find some of the other demon clans because he wanted to try to learn some of their techniques and do some tests with their blood.